Tree Morphology – a continuing story…

A one-day seminar held on
June 15th 2007 at
The University of the
West of England, Bristol

This seminar, presented by Treework Environmental Practice in association with the Arboricultural Association, continued on the good work of an initial two-day Morphology seminar held in March 2006. This day marked Seminar VII in the ongoing series exploring the outer reaches of arboriculture brought to us by Treeworks Environmental Practice’s supremo Neville Fay.

Neville started proceedings, stating that morphology is likely to have passed us by in our training years but that, by understanding a tree’s form and processes we will increase our understanding and diagnostic skills. The aim is therefore to inform our work, and for Treeworks Environmental Practice this is especially relevant with veteran trees.

The aging process is both an ontogenetical and a physiological response – and combines patterns of ‘prescribed norms’ with the body language of adaptive growth. Our study of perturbations to the norm can make a powerful diagnostic tool.

By appreciating and enjoying these adaptations we can learn to challenge traditional concepts of form and formality. What was once considered valueless tells a tale of history and regeneration, once our eyes are unlocked. This applies not just to the ancient pollard but also the less conventionally perfect specimen, rarely allowed to survive in a heavily managed tree population (I put a good part of the blame for this on the British Standards for nursery stock! It seemed such a good idea at the time…but then so did dead wooding and heavy thinning and hopefully we have educated ourselves out of that).

The “Urpflanze” – Goethe’s archetypal plant concept form, from which all plants are derived – a morphological plant patent?

During a guided tour through the history of tree morphology, while reviewing aspects of the previous seminar it was a pleasure to revisit Leonardo and Goethe, the Golden Ratio and the Fibonacci sequence. The latter can be found on a limitless scale, from the double helix of DNA to the working of constellations. It is a growth form not a fixed bilateral symmetry, and well illustrated by the spiralling contortions that many plants display in their leaf angle (137.5 degrees) to maximise sunlight collection.

Neville then introduced the legendary Professor Francis Hallé, Professor of Botany at the University of Montpellier. Famous for landing inflatable contraptions on the canopy of tropical rainforest trees and having worked in that environment for 40 years, his first session was a historical approach to tree architecture, paying tribute to the British and European tradition of scientific tree drawing from the 16th – 18th centuries.

Early plant illustration gave way to an ever closer examination of vegetative parts (flowers and fruits), then anatomy, meristems and cells – finally down to chromosomes and genes. The smaller the focus the less obvious the tree architecture, and for Hallé the macro view of tropical trees, less complicated being in a relatively benign growing environment, illustrates his subject best.

Expanding on the ontogenetical v physiological theme, Hallé pointed out that a young tree displays its genetic inheritance perfectly, showing a regular and easily illustrated architecture that in time becomes chaotic visually as the likes of gravity, frost, fire and all the other environmental factors make their mark.

Along with Roelof Oldeman, Hallé concluded earlier in his career that all trees conform to one of some 20 architectural models; a theme developed later the second speaker.

Neville then introduced the legendary Professor Francis Hallé, Professor of Botany at the University of Montpellier. Famous for landing inflatable contraptions on the canopy of tropical rainforest trees and having worked in that environment for 40 years, his first session was a historical approach to tree architecture, paying tribute to the British and European tradition of scientific tree drawing from the 16th – 18th centuries.

Early plant illustration gave way to an ever closer examination of vegetative parts (flowers and fruits), then anatomy, meristems and cells – finally down to chromosomes and genes. The smaller the focus the less obvious the tree architecture, and for Hallé the macro view of tropical trees, less complicated being in a relatively benign growing environment, illustrates his subject best.

Expanding on the ontogenetical v physiological theme, Hallé pointed out that a young tree displays its genetic inheritance perfectly, showing a regular and easily illustrated architecture that in time becomes chaotic visually as the likes of gravity, frost, fire and all the other environmental factors make their mark.

Along with Roelof Oldeman, Hallé concluded earlier in his career that all trees conform to one of some 20 architectural models; a theme developed later the second speaker.

More Seminar Reviews can be read here >> Treeworks Environmental Practice Tree Seminar Reviews